1. Field of the Invention
The present invention relates to a sheet conveying device comprising a positioning member configured to place sheets held in a tray in position and an image recording apparatus including the sheet conveying device.
2. Description of Related Art
Known sheet conveying devices separate sheets stacked in a tray one by one and convey the sheets to a recording section. In such sheet conveying devices, as a pickup roller is driven with its roller surface contacting a sheet, sheets are conveyed from the tray to a predetermined conveying direction while being separated one by one by friction. A known sheet conveying device includes a pickup roller rotatably supported at an end of an arm, which is configured to move pivotally. In the sheet conveying device, a few sheets remaining in the tray may be conveyed simultaneously. Feeding of a plurality of sheets simultaneously may be called multiple sheet feeding. To prevent multiple sheet feeding by reliably separating sheets, a friction member having a predetermined frictional coefficient is positioned on a sheet mounting surface of the tray. The friction member is positioned to face the pickup roller on the sheet mounting surface. The friction member will reduce the possibility of multiple sheet feeding because the frictional force applied between the tray and the sheets becomes greater than the frictional force applied between the sheets.
When the tray becomes empty as the last one sheet remaining in the tray is conveyed, the pickup roller and the friction member contact each other. In this case, contact and friction between the pickup roller and the friction member apply excessive loads to the pickup roller. To prevent excessive load to the pickup roller, a known image recording apparatus, e.g., an image recording apparatus described in U.S. Patent Application Publication No. 20070081199, corresponding to Japanese Laid-Open Patent Publication No. 2007-62965, discloses a moving device configured to raise the pickup roller away from the friction member when the tray becomes empty. The moving device reduces excessive loads applied to the pickup roller.
However, the sheet conveying device including the moving device may not convey sheets, depending on the sizes of sheets in the conveying direction, as the moving device raises the pickup roller before the leading edge of a sheet reaches a conveying device positioned downstream of the pickup roller in the conveying direction.